From 77391c6e58599b2106f4293bdc595de24f1b8e0d Mon Sep 17 00:00:00 2001
From: Samuel Esposito <40698384+samuel-esp@users.noreply.github.com>
Date: Mon, 30 Jun 2025 20:27:44 +0200
Subject: [PATCH] fix: correctly assign health check protocol when annotation
 value is lowercase

---
 pkg/providers/v1/aws_loadbalancer.go |  4 ++--
 pkg/providers/v1/aws_test.go         | 13 +++++++++++++
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/pkg/providers/v1/aws_loadbalancer.go b/pkg/providers/v1/aws_loadbalancer.go
index 9b0fd9985e..9080395f1b 100644
--- a/pkg/providers/v1/aws_loadbalancer.go
+++ b/pkg/providers/v1/aws_loadbalancer.go
@@ -1385,7 +1385,7 @@ func (c *Cloud) ensureLoadBalancerHealthCheck(ctx context.Context, loadBalancer
 	actual := loadBalancer.HealthCheck
 	// Override healthcheck protocol, port and path based on annotations
 	if s, ok := annotations[ServiceAnnotationLoadBalancerHealthCheckProtocol]; ok {
-		protocol = s
+		protocol = strings.ToUpper(s)
 	}
 	if s, ok := annotations[ServiceAnnotationLoadBalancerHealthCheckPort]; ok && s != defaultHealthCheckPort {
 		p, err := strconv.ParseInt(s, 10, 0)
@@ -1394,7 +1394,7 @@ func (c *Cloud) ensureLoadBalancerHealthCheck(ctx context.Context, loadBalancer
 		}
 		port = int32(p)
 	}
-	switch strings.ToUpper(protocol) {
+	switch protocol {
 	case "HTTP", "HTTPS":
 		if path == "" {
 			path = defaultHealthCheckPath
diff --git a/pkg/providers/v1/aws_test.go b/pkg/providers/v1/aws_test.go
index 1feb780fc9..69a823f869 100644
--- a/pkg/providers/v1/aws_test.go
+++ b/pkg/providers/v1/aws_test.go
@@ -2192,6 +2192,19 @@ func TestEnsureLoadBalancerHealthCheck(t *testing.T) {
 				Target:             aws.String("TCP:8080"),
 			},
 		},
+		{
+			name: "healthcheck protocol written lowercase should be converted to uppercase",
+			annotations: map[string]string{
+				ServiceAnnotationLoadBalancerHealthCheckProtocol: "tcp",
+			},
+			want: elbtypes.HealthCheck{
+				HealthyThreshold:   aws.Int32(2),
+				UnhealthyThreshold: aws.Int32(6),
+				Timeout:            aws.Int32(5),
+				Interval:           aws.Int32(10),
+				Target:             aws.String("TCP:8080"),
+			},
+		},
 	}
 	lbName := "myLB"
 	// this HC will always differ from the expected HC and thus it is expected an